1. Field of the Invention
The present invention relates to an electric connector and electric connector assembly with a fit-in structure for electrically connecting any appropriate signal transmission medium to a main wiring board.
2. Description of the Related Art
In general, in various electric devices and others, an electric connector is widely used for connecting a terminal part of a signal transmission medium formed of a flexible printed circuit (FPC), a flexible flat cable (FFC), a coaxial cable, or others to a main printed wiring board. The electric connector is configured in a manner such that, to a first connector (a receptacle connector) mounted on a main printed wiring board, a second connector (a plug connector) to which a signal transmission medium such as a coaxial cable is inserted and both of the connectors fit in together. Signal transmission is performed though conductive contacts (conductive terminals) arranged in a multipolar manner inside a body housing.
In this electric connector, to reduce an influence of external electromagnetic noise on a transmission signal or to reduce electromagnetic noise emitted toward the outside, the structure has been conventionally adopted such that the outer surface of the body housing is covered with a metal-thin-plate-like conductive shell for electromagnetic shielding (refer to Japanese Unexamined Patent Application Publication No. 2007-73426).
However, the conventional electric connector has the structure such that only the outer surface of the body housing is covered with the conductive shell, and the terminal part of the conductive contacts (conductive terminals) described above, more specifically, a connecting portion with the main wiring board, is not covered with the conductive shell and is exposed to the outside. Therefore, with an increase in frequency of the transmission signal particularly in recent years, the influence of external electromagnetic noise on the connecting portion with the main wiring board has been becoming impossible to ignore, and the possibility of emission of electromagnetic noise from the connecting portion to the outside has been increasing.
Note that, conventionally, a conductive tape is affixed to the connecting portion between the conductive contacts and the main wiring board, or the conductive shell is extended to cover that portion. When the conductive tape is used, however, a relatively bothersome working process of affixing the conductive tape is added, and therefore productivity tends to decrease. Moreover, when the conductive shell is extended for coverage, the connecting portion between the conductive contacts and the main wiring board cannot be checked by a visual inspection, an image inspection, or the like, thereby disadvantageously making it difficult to conduct an inspection and a check to see whether the connection works without any trouble.
Furthermore, in the conventional electric connector, a ground bar may be used to connect a plurality of coaxial cables arranged in a multipolar manner for spreading, and part of the conductive shell may be soldered to that ground bar. At the time of solder connection between the conductive shell and the ground bar, a flux contained in a solder material is abruptly blown due to heating of the solder material, and therefore the solder material and the flux scatter to be adhered to a portion other than the originally-intended connecting portion, for example, a contact portion of the conductive contacts, thereby possibly causing an electrical problem.